VI treatment of whole potatoes (Toyoshiro and Irish Cobbler)
was carried out in a 10% ascorbic acid solution. A mass ratio, of
the solution to potato, of 3% w/w was used to ensure adequate
immersion and minimise the dilution effect on the concentration
of VI solution (Sormani, Maffi, Bertolo, & Torreggiani, 1999). A vacuum
pressure of 9.33 kPa was applied to the system for 0–60 min,
and atmospheric pressure restoration for 3 h.Whole potatoes were
drained, rinsed with distilled water to remove the attached solution,
and gently blotted with tissue papers. Ascorbic acid contents
of impregnated and untreated (fresh as control) potatoes were analysed
immediately.